1. Field of the Invention
This invention relates to plasticizers for liquid crystal display (LCD) films. More particularly, this invention relates to compositions comprising plasticizers that improve the elevated temperature properties of cellulose esters and films made from the cellulose ester compositions.
2. Background of the Invention
Triphenyl phosphate (TPP) is the primary plasticizer used in many liquid crystal display (LCD) films. A plasticizer system is needed to retain a sufficient glass transition temperature (Tg) for the film without making the film too stiff. Trioctyl trimellitate (TOTM) and diundecyl phthalate (DUP) are high boiling plasticizers mainly used in polyvinyl chloride (PVC). Plasticizers typically reduce Tg for films as the flexibility of the film is increased.